The present invention relates to the improvements in mining apparatus and more particularly to improvements in roof bolting equipment.
Perhaps the single most important consideration and challenge facing miners and mining engineers since the inception of underground mining involves the need to prevent the collapsing of the overhead ceilings or roofs and side walls (xe2x80x9cribsxe2x80x9d) of mines to prevent injury to personnel and catastrophic damage to mining equipment.
Roof bolting and rib bolting are those processes which secure the ribs, side walls and roofs of mines to other stable strata. These processes are relatively slow and are the main causes for preventing mines from advancing at a faster rate.
A currently acceptable method for supporting the roof of a mine entry involves drilling holes at predetermined intervals into the ceiling and ribs and installing elongated retaining bolts in the holes. Such bolts are commonly used in connection with retaining plates and support members. Such apparatus serves to secure together thin strata or bands of rock located adjacent the ribs and roofs and prevent lateral shifting of the strata, as well as, in some instances, to anchor the strata to more massive overlying rock. The installation of retaining bolts into the roof of a mine additionally requires the use of temporary roof support cylinders to support the roof as the bolt holes are being drilled. The reader will appreciate that during the initial engagement between the temporary cylinders and the unsupported section of roof, the condition exists for causing portions of the unsupported roof to fall. Thus, it is desirable for the operation personnel to be as far away from such apparatus as practical during its initial installation.
Over the years, a variety of different types of apparatuses have been developed for installing retaining bolts into the roof and ribs of a mine. An early roof bolting drill is disclosed in U.S. Pat. No. 2,771,273 to Pond. That device comprises an electrical powered drill assembly that is adapted to be manually pulled throughout the mine. Such device offers little protection from roof falls and falling debris during bolt installation.
In an effort to increase the speed of roof bolting, one prior art track mounted roof bolting apparatus was developed, known as the REMB (rapid entry mobile bolter) and was discussed and published in World Mining Equipment April 1997 issue (published by Independent Editorial and Technical Services of the UK). The REMB provides four vertically oriented roof bolting rigs on a forward moveable and raiseable carriage and work platform which is connected to a platform mounted above a track vehicle and which remains stationary relative to the track vehicle. The roof bolting work platform is connected to the stationary platform by a passageway and a series of steps. The bolting carriage and the work platform are attached to the track vehicle by a complex parallel linkage arrangement to the front of the vehicle, so as to keep the rigs at a 90xc2x0 degree angle at all times to the tracks as carriage, work platform and the rigs move up or down. The machine also includes a rib bolt rig behind each operator, which are mounted on the lower stationary platform. The bolting rigs are in a forward position relative to the two operators.
While the REMB has improved the speed of mining, it is not fast enough for many mining applications. One reason for this is the fact that the rib bolters are positioned on the platform which is stationary relative to track vehicle, and this platform is a separate platform from the platform where the operator will control and operate the four roof bolters. This causes several difficulties. The first is that there is a risk to injury for the operators to move up and down steps on platforms, particularly when the steps and the platforms may have water falling thereon making surfaces slippery, even if expanded metal mesh is provided.
The second difficulty relates to the fact that the operators have a bolting down-time as they move from the roof bolting platform to the rib bolting platform.
The REMB also inherently requires the double handling of the consumables as the operator must move a supply of the consumables to the roof bolting platform from the storage area on the REMB, to an area accessible by the operator on the roof bolting platform. This will entail the regular walking up and down to steps to and from the roof bolting platform.
Other prior art roof bolting apparatus mount bolting rigs onto swingable booms. Such equipment however generally form crush points which are hazardous to operators.
A continuous mining machine normally includes a rotatable cutting drum that is mounted on the front end of the mining machine. As the mining machine is advanced into the seam, the cutting drum dislodges or xe2x80x9cwinsxe2x80x9d the coal from the seam. In most continuous mining machines of this type, the won material is conveyed rearwardly of the cutting drum by a longitudinally extending conveyor that may discharge into self-propelled shuttle cars or other mobile conveying apparatuses to transport the won material from the mine face. The mining machine continuously advances into the seam and, as the material is won therefrom, an xe2x80x9centryxe2x80x9d is formed in the underground seam.
While some continuous mining equipment such as that disclosed in U.S. Pat. No. 4,655,507, published and issued on Apr. 7, 1987, have multiple roof bolting rigs mounted thereon, they invariably have a series of roof bolters and rib bolters mounted thereon to provide the full range of roof bolting facilities. However, such equipment can have the same disadvantages as the REMB has due to similar construction features. The continuous miners may have some four operators working to maintain the speed of roof bolting, but the use of two additional operators is a very costly solution to the speed requirements.
Other retaining bolt installation apparatuses are adapted to be affixed to a continuous mining machine for travel therewith. U.S. Pat. No. 3,493,058 to Zitko and U.S. Pat. No. 4,953,914 to LaBegue disclose such devices which can be operated by personnel located on the mining machine. While such apparatus do not require the mining machine to be removed from the entry while bolts are being installed, the mining process is, nonetheless, typically interrupted during the bolting process.
In the cut and flit method of mining, a continuous miner first proceeds down one road, it must then reverse out and turn down a second road and cut that road while a specialised roof bolter bolts in the first mentioned road. The bolter and the continuous miner are continually swapping their roadway positions as the mine face moves forward. The speed of moving forward however is generally limited to the speed of inserting bolts into the ribs and roof of the mine.
The present invention provides a mining apparatus for installing bolts into a mine entry, said apparatus including:
a frame having a forward end, a rearward end and lateral sides,
an upstanding bolter support wall attached to said forward end of said frame;,
a laterally extending guide frame mounted to said support wall which extends along a lateral plane which is generally parallel to the support wall;
at least one bolting rig slidably mounted to said guide frame; and translation means for selectively moving the bolting rig laterally along the guide frame relative to the support wall.
Preferably the bolting rig is mounted to the guide frame via a rotatable connection, the axis of rotation of the rotatable connection extending generally perpendicularly to said lateral plane, a rotary actuator connected to said bolting rig adapted to selectively control the rotation of the bolting rig through a range of angles between generally vertical orientation and generally horizontal orientation to allow for both roof and rib bolting operations.
The guide frame can include a pair of parallel laterally extending piston and cylinder assemblies, the cylinders each having a proximate end adjacent to the centre of the support wall and having cylinder axis extending laterally and generally horizontal, the bolting rig being mounted to a pair of pistons which are located within respective cylinders and slidable out of the distal ends of said cylinders.
The bolter support wall can include a plurality of rigidly interconnected beam and column members to which said guide frame is mounted.
Preferably the apparatus includes at least three bolting rigs mounted to the support wall including at least one central bolting rig and at least two side bolting rigs on opposite sides of the central bolting rig, the side bolting rigs each being mounted on laterally extending guide frames and being moveable relative to the support wall along said lateral plane.
Preferably the central bolting rig is tiltable in a vertical plane which is perpendicular to said lateral plane and is tiltable in said lateral plane through an angle of approximately 30xc2x0.
It is preferred that there are a pair of central bolting rigs side by side with each other, the central bolting rigs being aligned with said side bolting rigs.
Both central bolting rigs can be independently tiltable in said lateral plane each through an angle of approximately 30xc2x0 from an inclined angle of approximately 10xc2x0 in an inward direction, past vertical to an inclined angle of approximately 20xc2x0 in an outward direction said bolting rigs being lockable and operable in any selected angle of tilt within that range.
The mining apparatus can include a pair of drive units on opposite sides of the frame for carrying and moving the frame, a pivot assembly connecting the rearward end of the frame to each of the drive units, the pivot assembly defining a laterally extending pivot axis which is generally horizontal, the frame being pivotable relative to said drives about said pivot axis, said bolting rig adapted to be raised and lowered by pivoting the frame relative to the drive units about the pivot axis.
The mining apparatus can also include at least one deck extension platform pivotally attached to at least one side of said frame, said deck extension being pivotable between a first position in which it is generally co-planar with said deck, and a second position.
It is preferred that the frame has a push blade operably attached to the forward and thereof.
The apparatus can include at least one roof support member which is attached to the forward end of the frame for selectively supporting said mine entry as bolts are installed therein in use.
The mining apparatus provides a substantially flat work area rearward of said bolter support wall and said roof support member and an operator station located rearward of said work area, said roof support member being operable from said operator station.
A cable reel is preferably operably attached to said frame for selectively storing and paying out a power cable attached between said apparatus and a power source.
Preferably at least one said bolting rig is rotatably mounted to said frame such that said bolting rig can be rotated to a lateral position at which said bolting rig is adapted to install bolts in said side wall.
The frame can have an upstanding bolting rig support wall attached to the forward end thereof, a guide frame mounted to said support wall, said bolting rig being selectively movable laterally along said guide frame parallel to said bolting rig support wall.
The mining apparatus can further include at least one roof support member which includes a dual acting hydraulic cylinder arranged to engage a roof of said entry and a floor of said entry and extend therebetween to support said entry roof and retain said frame in position during installation of bolts.
Preferably said bolting rig is adapted to be manually operated by a control station attached thereto.
The mining apparatus moist preferably includes a plurality of bolting rigs and each said bolting rig is independently manually operable by means of a control station attached thereto.
An operator station can be provided on said frame for supporting an operator thereon during an operation of said bolting rig, a work area being defined between said operator station and said bolting rig, and a return oil tank being incorporated into said frame, said tank having a generally planar upper surface which forms part of said work area.